How do i use timer function properly

Question

I have been trying to make an easy incremental game, just to learn, and i couldnt figure out how to use timer to give the user "coins" every second. This question might have been asked a lot but all the solutions tutorials etc i read were too hard/outdated/not valid for my case.

edit: current code

import Foundation
import Darwin
//vars
var copperCoins = 0
var copperGrowth = 1

//intro
print("Simple incremental game!")

print("Copper coins: \(copperCoins)")
//while runs
while true
{
    let timer = Timer.scheduledTimer(withTimeInterval: 1.0, repeats: true) { timer in
        copperCoins += copperGrowth
    }
}

Could you be a little more specific? Maybe some code you've already written? — lancylot2004, Aug 22 '22 at 16:42

score 1 · Accepted Answer · answered Aug 22 '22 at 16:53

1

Darwin is not needed, and the while loop is not needed either

Create a strong reference to the timer to be able to modify it for example to stop and recreate the timer.

This runs 20 times and then invalidates the timer.

import Foundation

var copperCoins = 0
var copperGrowth = 1

//intro
print("Simple incremental game!")

print("Copper coins: \(copperCoins)")
var timer: Timer?

timer = Timer.scheduledTimer(withTimeInterval: 1.0, repeats: true) { timer in
    copperCoins += copperGrowth
    print(copperCoins)
    if copperCoins >= 20 { timer.invalidate() }
}

answered Aug 22 '22 at 16:53

vadian

274,689
30
353
361

while running this the copper coins dont get modified as expected. my console: Simple incremental game! Copper coins: 0 Program ended with exit code: 0 – Nanometer Aug 22 '22 at 17:00
https://stackoverflow.com/questions/31944011/how-to-prevent-a-command-line-tool-from-exiting-before-asynchronous-operation-co is probably helpful – Shadowrun Aug 22 '22 at 17:06
1

To run the code in a "Terminal" app you need a runloop or use Swift Concurrency. – vadian Aug 22 '22 at 17:06
@vadian. thanks. But the answer you provided doesnt modify the copper coin value. – Nanometer Aug 22 '22 at 17:15
It does, please try the code in a Playground. – vadian Aug 22 '22 at 17:16
@vadian im not using a playground cuz of readLine(), but i realised i have to do timer.fire(). thanks for the help! – Nanometer Aug 22 '22 at 17:17

score 0 · Answer 2 · answered Aug 22 '22 at 16:53

First, you've got a forever-loop which creates loads of timers but never uses them - this might not be good. You only need to create it once, then use it.

let timer = Timer.scheduledTimer(withTimeInterval: 1.0, repeats: true) { timer in
    copperCoins += copperGrowth
    print(copperCoins)
}

Second, a timer needs to be started: timer.fire(), which should go outside.

But the last one - timers are usually used in apps to... time stuff. if you're doing this in a playground or just one script, the code will probably fire the timer once and just stop, since it's finished executing.

This I'm not sure but I think you can use a loop at the end to keep the code going:

while true {
    if copperCoins > 100 { break }
}

At the end, which means your code will only stop once copperCoins reaches 100. Probably not the best way to test timers in playground, but in any case this might be a problem.

Hope this helps.

while running this the copper coins dont get modified as expected. my console: Simple incremental game! Copper coins: 0 Program ended with exit code: 0 — Nanometer, Aug 22 '22 at 17:03
Don't forget the `timer.fre()` - exit code 0 usually means programme exited with no issues (as far as the computer can tell). — lancylot2004, Aug 22 '22 at 19:40

How do i use timer function properly

2 Answers2